A Hong Kong hedge fund with one of Europe’s biggest short positions on record reaped massive returns on the bet as the rocky ride in oil prices dragged down shares of UK stock Premier Oil. 

Asia Research and Capital Management, or ARCM, held a position representing about 17% of Premier Oil shares. The historic plummet in oil prices last week battered the shares of oil companies, as well as pulling down almost every other sector with it. Premier Oil is down around 73% this year.